Percutaneous ports with wire coils

ABSTRACT

The various implementations described herein include a percutaneous port for promoting tissue in-growth around the percutaneous port. In one aspect, the percutaneous port includes a tubular structure having an outer surface, and a coil having an outer surface and comprised of a plurality of loops. Furthermore, at least a portion of the outer surface of the coil is joined to the outer surface of the tubular structure.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/061,602, filed Oct. 8, 2014, the contents of which are incorporatedherein by reference in its entirety.

TECHNICAL FIELD

The disclosed embodiments relate generally to a medical device, and moreparticularly to a percutaneous port with wire coils that promote tissuein-growth around the port.

BACKGROUND

Modern medicine often requires prolonged or repeated access to theinterior of a patient's body. For example, treatment of a patient mayrequire access to a patient's vascular system to, for example, providetherapeutic agents thereto and/or remove fluids therefrom.

Continuous access to the interior of a patient's body may be providedthrough a port surgically implanted through the patient's skin. Theseports are otherwise known as percutaneous ports.

Conventional percutaneous ports, however, often result in poor tissueintegration around the surface of the port, which can lead to infectionand even inadvertent port removal.

Accordingly, there is a need to provide a percutaneous port that betterintegrates with the surrounding tissue.

SUMMARY

According to some embodiments, a percutaneous port is manufactured byjoining at least a portion of the outer surface of a coil to the outersurface of a tubular structure. More specifically, some embodimentsinclude a method of manufacturing a percutaneous port for promotingtissue in-growth around the percutaneous port by providing a tubularstructure having an outer surface, and providing a coil having an outersurface and comprised of a plurality of loops. The method furtherincludes joining at least a portion of the outer surface of the coil tothe outer surface of the tubular structure.

In some embodiments, the method further comprises winding the coilaround the tubular structure in a spiral, prior to the joining.

In some embodiments, the joining comprises brazing at least a portion ofthe outer surface of the coil to the outer surface of the tubularstructure. Furthermore, in some embodiments, brazing is performed for apredefined period of time that is based at least in part on a thicknessof the wire comprising the coil, a thickness of the outer surface of thetubular structure, and a predefined brazing temperature.

In some embodiments, the outer surface of the tubular structurecomprises a plated material, and the coil comprises a coil material,wherein the plated material and the coil material are chemicallyreactive with one another.

In some embodiments, the coil comprises a material selected from thegroup consisting of titanium and its alloys, nitinol, tungsten and itsalloys, molybdenum and its alloys, niobium and its alloys,cobalt-chromium based alloys, noble metals, such as platinum, iridium,palladium, silver, gold, and their alloys, and medical grade stainlesssteel.

In some embodiments, the tubular structure is made from titanium, andthe outer surface of the tubular structure is made from nickel.

In some embodiments, the coil is formed by providing a center rod,winding a wire around the center rod, and removing the center rod.Furthermore, in some embodiments, removing the center rod occurs afterjoining at least a portion of the outer surface of the coil to the outersurface of the tubular structure. In some embodiments, removing thecenter rod includes etching away the center rod using a chemicaletchant. Furthermore, in some embodiments, the center rod is selectedfrom the group consisting of molybdenum and tungsten, and the chemicaletchant is selected from the group consisting of sodium phosphate,aqueous ferric chloride, an aqueous ferricyanide ion solution, a solublemolybdate, and a soluble tungstate.

In some embodiments, the method further comprises providing anadditional coil having an outer surface and comprised of a plurality ofloops and winding the additional coil around the tubular structure in aspiral. At least a portion of the outer surface of the additional coilis joined to the outer surface of the tubular structure, the loops ofthe coil having a first diameter and the loops of the additional coilhaving a second diameter, wherein the first diameter is significantlylarger than the second diameter. In some embodiments, the additionalcoil is interleaved between the coils.

In some embodiments, the longitudinal axis of the coil is substantiallyparallel to the longitudinal axis of the tubular structure.

In some embodiments, after joining, at least some of the loops of thecoil are oriented at an angle to the outer surface of the tubularstructure. Furthermore, in some embodiments, the angle to the outersurface of the tubular structure is substantially perpendicular.Moreover, in some embodiments, the at least some of the loops of thecoil are further oriented at an angle substantially parallel to thelongitudinal axis of tubular structure.

In some embodiments, a predefined spacing between adjacent loops in thecoil is variable.

In some embodiments, the tubular structure is cylindrical, while inother embodiments, the tubular structure is not cylindrical.

Another aspect includes the percutaneous port for promoting tissuein-growth around the percutaneous port, which comprises a tubularstructure having an outer surface, and a coil having an outer surfaceand comprised of a plurality of loops, wherein at least a portion of theouter surface of the coil is joined to the outer surface of the tubularstructure.

In some embodiments, a cross section of the tubular structure iscircular, square, rectangular, or polygonal.

In some embodiments, the coil forms a spiral around the tubularstructure. Furthermore, some embodiments further include an additionalcoil having an outer surface and comprised of a plurality of loops,wherein the additional coil also forms a spiral around the tubularstructure. In such embodiments, the plurality of loops of the coil has asubstantially larger diameter than the plurality of loops of theadditional coil. Furthermore, in some embodiments, the spiral formed bythe additional coil is interleaved with the spiral formed by the coil.

In some embodiments, after joining, at least some of the plurality ofloops are oriented so as to form an angle with the outer surface of thetubular structure.

In some embodiments, the at least a portion of the outer surface of thecoil is brazed to the outer surface of the tubular structure.

In some embodiments, the outer surface of the tubular structurecomprises a plated material, and the coil comprises a coil material,wherein the plated material and the coil material are chemicallyreactive with one another.

In some embodiments, the coil comprises a material selected from thegroup consisting of titanium and its alloys, nitinol, tungsten and itsalloys, molybdenum and its alloys, niobium and its alloys,cobalt-chromium based alloys, noble metals, such as platinum, iridium,palladium, silver, gold, and their alloys, and medical grade stainlesssteel.

In some embodiments, the tubular structure is made from titanium.

In some embodiments, the outer surface of the tubular structure is madefrom nickel.

In yet another aspect, a percutaneous port for promoting tissuein-growth around the percutaneous port comprises a plate having opposingsubstantially flat first and second surfaces, wherein the plate definesa hole there through, and a coil having an outer surface and comprisedof a plurality of loops, wherein at least a portion of the outer surfaceof the coil is joined to the first surface of the plate around the hole.

In some embodiments, the plate is circular, square, rectangular, orpolygonal shaped.

In some embodiments, the coil forms a spiral around the hole of theplate. Furthermore, in some embodiments, the percutaneous port furthercomprises an additional coil having an outer surface and comprised of aplurality of loops, wherein the additional coil forms an additionalspiral around the hole of the plate. The spiral has a first spiraldiameter, and the additional spiral has a second spiral diameterdistinct from the first spiral diameter. Furthermore, the plurality ofloops of the coil have a first loop diameter, and the plurality of loopsof the additional coil has a second loop diameter distinct from thefirst loop diameter. In some embodiments, the spiral formed by the coilis interleaved with the additional spiral formed by the additional coil.

In some embodiments, after joining, at least some of the plurality ofloops are oriented so as to form an angle with the first surface of theplate.

In some embodiments, the at least a portion of the outer surface of thecoil is brazed to the first surface of the plate. Furthermore, in someembodiments, the first surface of the plate comprises a plated material,and the coil comprises a coil material, wherein the plated material andthe coil material are chemically reactive with one another.

In some embodiments, the coil comprises a material selected from thegroup consisting of: titanium and its alloys; nickel and its alloys;nitinol; medical-grade stainless steel; silver; and noble metalsincluding platinum, gold, iridium, and their alloys.

In some embodiments, the plate is made from titanium.

In some embodiments, the first surface of the plate is made from nickel.

Numerous details are described herein in order to provide a thoroughunderstanding of the example implementations illustrated in theaccompanying drawings. However, some embodiments may be practicedwithout many of the specific details, and the scope of the claims isonly limited by those features and aspects specifically recited in theclaims. Furthermore, well-known methods, components, and circuits havenot been described in exhaustive detail so as not to unnecessarilyobscure more pertinent aspects of the implementations described herein.

The embodiments described herein offer significant advantages overtraditional techniques and designs. For example, conventional ports usemesh-like textures on the outside surface of the ports. These designs donot adequately penetrate into surrounding tissue, and poorly integratewith a patient's body, thereby increasing the risk of port removal andinfection. Unlike conventional ports, the embodiments disclosed herein(e.g., that include coils), facilitate a deeper depth of penetrationinto surrounding tissue, for more effective, robust, and longer lastingtissue in-growth. As such, the percutaneous ports described herein arestrongly anchored to the surrounding tissue, thereby greatly reducingthe risk of port removal and infection.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the present disclosure can be better understood, a detaileddescription is provided below that makes reference to features ofvarious embodiments, some of which are illustrated in the appendeddrawings. The appended drawings, however, merely illustrate the morepertinent features of the present disclosure and are not intended tolimit the scope of the invention.

FIG. 1A is an oblique view of an embodiment of a percutaneous port.

FIG. 1B is a side cross-sectional view of the percutaneous port shown inFIG. 1A.

FIG. 1C is a close-up of the cross-sectional view shown in FIG. 1B.

FIG. 2A is an oblique view of another embodiment of a percutaneous port.

FIG. 2B is a side cross-sectional view of the percutaneous port shown inFIG. 2A.

FIG. 2C is a close-up of the cross-sectional view shown in FIG. 2B.

FIGS. 3A-3D are flowcharts of a method of manufacturing a percutaneousport, in accordance with some embodiments.

FIGS. 4A-4N are perspective views of a percutaneous port during variousstages of manufacture, in accordance with some embodiments.

In accordance with common practice the various features illustrated inthe drawings may not be drawn to scale. In addition, some of thedrawings may not depict all of the components of a given method orapparatus. Finally, like reference numerals may be used to denote likefeatures throughout the specification and figures.

DETAILED DESCRIPTION

The following is a detailed description of various embodiments ofpercutaneous ports and their method of manufacture.

FIGS. 1A-1C illustrate multiple views of a percutaneous port 100 inaccordance with some embodiments. Specifically, FIG. 1A is a perspectiveview of an embodiment of a percutaneous port 100; FIG. 1B is a sidecross-sectional view of the percutaneous port 100 shown in FIG. 1A; andFIG. 1C is a close-up of the cross-sectional view shown in FIG. 1B.

The percutaneous port 100 includes a tubular structure 102, coils 104,and optionally, an additional tubular structure 106. More specifically,the tubular structure 102 is formed from a wall 116 that encloses acavity or chamber 108. In some embodiments, the wall 116 has a thicknessof between 0.1-25.4 mm. The wall 116 has an inner surface 116(a) and anouter surface 116(b) (best seen in FIG. 1C). As explained below, thecoils 104 are joined to the outer surface 116(b).

As shown in FIG. 1B, in some embodiments, the percutaneous port 100further forms a first opening 110 and a second opening 112. In someembodiments, these openings 110, 112 are disposed opposite to oneanother. In some embodiments, the first opening 110 is significantlylarger than the second opening 112.

In some embodiments, an additional tubular structure 106 is coupled tothe tubular structure 102, as shown in FIG. 1B. The additional tubularstructure 106 is formed from a wall that encloses an additional cavityor chamber. In some embodiments, the wall of the additional tubularstructure 106 has the same thickness as the wall 116 of the tubularstructure 102, while in other embodiments it has a tapering thickness asshown. In some embodiments, the additional tubular structure 106 sharesan opening 112 with tubular structure 102, and has an opening 114opposite to the opening 112.

In some embodiments, the additional tubular structure 106 enables deeperpenetration of the port into the tissue of a subject or patient, whilealso defining an additional chamber for further isolating outsidecontaminants from reaching the subject, thus better preventinginfection.

In embodiments that include both the tubular structure 102 and theadditional tubular structure 106, the percutaneous port 100 forms afunnel from the wider opening 110 to the narrower opening 114. In theseembodiments, a diameter (or equivalent dimension) of the tubularstructure 102 is significantly larger than a diameter (or equivalentdimension) of the additional tubular structure 106. In some embodiments,the diameter (or equivalent dimension) of the tubular structure 102 isbetween 1.0-50.8 mm, and the diameter (or equivalent dimension) of theadditional tubular structure 106 is between 0.1-20 mm.

The tubular structure 102 and/or the additional tubular structure 106have any suitable shape. While FIGS. 1A-1C illustrate a tubularstructure 102 that has a cylindrical shape and circular cross-section,any other suitable shapes may be employed. For example, in otherembodiments, the cross-sectional shape of the tubular structure 102and/or the additional tubular structure 106 taken along a planeperpendicular to their longitudinal directions, may be circular, square,rectangular, hexagonal, or polygonal. Moreover, the diameter (orequivalent dimension) of the tubular structure 102 and/or the additionaltubular structure 106 may taper along the longitudinal axis like afunnel.

In some embodiments, the tubular structure 102 and/or the additionaltubular structure 106 is made from a material selected from the groupconsisting of: titanium and its alloys, nitinol, tungsten and itsalloys, molybdenum and its alloys, niobium and its alloys,cobalt-chromium based alloys, noble metals, such as platinum, iridium,palladium, silver, gold, and their alloys, cobalt-chromium alloys,medical grade stainless steel, zirconia, alumina and their composites,and other biocompatible metallic or ceramic materials. In someembodiments, the outer surface 116 of the tubular structure 102 isplated with a brazing material used for joining the coils 104 to thetubular structure 102, a process described in greater detail below.Furthermore, in some embodiments, the outer surface 116 of the tubularstructure 102 comprises a material selected from the group of materialsthat can be used to join the coils to the tubular structure and formbiocompatible structure. They consist of: nickel, gold and nickel andtitanium alloys and nickel and titanium in the forms of laminates,pastes or thin films.

The coil 104 includes multiple individual loops, coils, or windings 120,as best seen in FIG. 1C. At least a portion of the coil 104 is joined toat least a portion of the outer surface 116 of the tubular structure 102using any suitable technique, such as brazing. In some embodiments, thecoil 104 has loops with a diameter of between 104-5000 um.

In some embodiments, at least a portion of an additional coil 118 isjoined to at least a portion of the outer surface 116 of the tubularstructure 102, as shown, using any suitable technique, such as brazing.As was the case with the coil 104, the additional coil also has multipleloops, coils or windings 121. In some embodiments, the additional coil118 is continuous, while in other embodiments, the additional coil 118includes multiple spaced apart sections (not shown).

In some embodiments, the coils 104 and/or 118 are continuous, while inother embodiments, the coils 104 and/or 118 includes multiple spacedapart sections (not shown). In some embodiments, for example, aplurality of individual, unconnected rings for joining to the outersurface 116 of the tubular structure 102 is provided. In someembodiments, the coils 104 and/or 118 are wound around the tubularstructure 102 in a spiral or larger coil, as shown. In otherembodiments, the coils 104 and/or 118 is joined to the tubular structure102 in any other suitable configuration, such as multiple parallel coilswith longitudinal axes that are parallel to the longitudinal axis of thetubular structure, i.e., coils 104 and/or 118 are arranged such that thecoils 104 and/or 118 are substantially parallel to the longitudinal axisof the tubular structure 102.

In some embodiments, the coils 104 and/or 118 have distinct loopdiameters from one another, form distinct spirals around the tubularstructure 102. In these embodiments, as shown in FIGS. 1A-1C, thedistinct spirals formed by the coil 104 and the additional coil 118 areinterleaved with one another. Furthermore, in some embodiments, as shownin FIG. 1C, a coil at least partially overlaps with an additional coilsuch that the plurality of loops of the coil is interleaved with theplurality of loops of the additional coil.

In some embodiments, the loops of the additional coil 118 have adiameter substantially smaller than the diameter of the coil 104. Forexample, as illustrated in FIG. 1C, the loops 120 of a coil 104 have adistinct loop diameter (e.g., 1000 um) that is substantially larger thanthe loop diameter of the loops 121 (e.g., 300 um) of the additional coil118. In some embodiments, the additional coil 118 has loops with adiameter between 25-1250 um. The loops 120, 121 can be formed intovariety of suitable shapes, including, but not limited to, a circle,square, rectangle, or polygon.

As the loop diameter determines the depth of penetration into thesurrounding tissue, the loop diameter for a respective plurality ofloops is determined based on the type of tissue in-growth intended forthe respective plurality of loops. For example, a smaller loop diameter(e.g., 25 to 300 um) allows better tissue in-growth with the dermis andepidermis, thus forming a better seal and reducing infection rates atthe skin. In contrast, a larger loop diameter (e.g., 200 to 1000 um)allows deeper penetration and better tissue in-growth with surroundingtissue, enabling stronger mechanical integration and thus bettermitigating issues of inadvertent port removal and exit site infection.Therefore, in some embodiments, such as that shown, two distinct loopdiameters are used together.

In some embodiments, each loop of a coil 104, 118 has a loop diameterdistinct from the loop diameter of adjacent loops within the same coil104, 118. For example, the loop diameter of successive loops 120 of acoil 104 alternates between 1000 um and 300 um.

In some embodiments, the additional coil 118 is wound around the tubularstructure 102 between each winding of the coil 104, as shown. In someembodiments, the additional coil 118 is also joined to the coil 104using any suitable technique, such as brazing.

In some embodiments, the coils 104, 118 are made from a materialselected from the group consisting of: titanium and its alloys, nitinol,tungsten and its alloys, molybdenum and its alloys, niobium and itsalloys, cobalt-chromium based alloys, noble metals, such as platinum,iridium, palladium, silver, gold, and their alloys, and medical gradestainless steel. Furthermore, in some embodiments, the material of thecoils 104 is chemically reactive with the material of the outer surface116 of the tubular structure 102.

In some embodiments, each loop of a coil 104, 118 has a predefinedspacing or pitch from adjacent loops in the respective coil 104. Thepredefined spacing or pitch determines the density of loops in arespective coil (e.g., a number of loops for a fixed length of a coil).For example, a coil having a length of 50 mm and a predefined spacing of0.5 mm between loops, will have a greater number (and thus, a greaterdensity) of loops than a different coil having the same length, but alarger predefined spacing of 1 mm between loops. Increasing the densityof loops in a respective coil 104 by adjusting the predefined spacingbetween the respective loops 118 enables improved tissue in-growth, aseach additional loop provides an additional anchor point for surroundingtissue and thus creates a stronger mechanical integration of thepercutaneous port 100. However, too small a pitch could prevent adequatetissue in-growth. In some embodiments, the predefined spacing betweenadjacent loops in a respective coil 104 is variable (e.g., thepredefined spacing between successive loops 118 alternates between 0.5mm and 1 mm), while in other embodiments, the predefined spacing isuniform (e.g., the predefined spacing between successive loops 118 is0.5 um).

In some embodiments, the loops 118, 120 are oriented at an angle to theouter surface 116 of the tubular structure 102. For example, asillustrated in FIGS. 1A-1C, the loops 118, 120 are oriented at an anglesubstantially perpendicular to the outer surface 116 of the tubularstructure 102. Optionally, in some embodiments, the loops 118, 120 areoriented so as to form two or more distinct angles. In a non-limitingexample, successive loops 118 in a respective coil 104 are oriented suchthat they form angles which alternate between a 45 degree angle and a135 degree angle. In some embodiments, the loops 118, 120 are furtheroriented such that the longitudinal axis of the loops are substantiallyparallel (i.e., vertically, as shown in FIGS. 1A-1C), or alternatively,substantially perpendicular (i.e., horizontally), to the longitudinalaxis of the tubular structure 102. In these embodiments, referring tothe perspective shown in FIG. 1B, the longitudinal axis is defined asthe axis running from the top (e.g., first port 110) of the tubularstructure 102 to the bottom (e.g., second port 112).

As described in greater detail below, the plurality of loops of the coil104 and/or additional coil 118 facilitates optimal tissue in-growtharound the port 100, enabling a stronger physical integration of theport 100 to the patient's tissue thereby mitigating issues such asinadvertent port removal and infection.

The percutaneous port 100 provides an interface enabling internal accessto a patient into which the percutaneous port 100 is implanted. Inparticular, the tubular structure 102, in combination with at least thefirst opening 110 and the second opening 112, define a conduit (e.g.,chamber 108) through which external components (e.g., electroniccontroller or fluid pump) can access internal components (e.g.,implanted sensors or the vascular system) of the patient. For example,when surgically implanted into a subject (not shown), the percutaneousport 100 serves as a physical access port for catheters (e.g., drug ormaterial delivery), cables (e.g., for power or signal transport), and/orother external or internal components and/or devices. Use of thepercutaneous port eliminates the need for subsequent surgical proceduresfor accessing the internal systems within a patient.

During a surgical procedure, the percutaneous port 100 is implanted intoa patient in such a way that the loops of the coils 104, 118 penetrateinto and are positioned between the tubular structure 102 and thesurrounding tissue. As the subject recovers from the procedure, newtissue grows through a lattice formed by the loops of the coils 104, 118thereby securely anchoring the port to the surrounding tissue. Thisgreatly reduces inadvertent removal and repositioning of thepercutaneous port 100, reduces irritation and infection at the surgicalsite, and shortens the recovery time.

FIGS. 2A-2C illustrate multiple views of another embodiment of apercutaneous port 200. Specifically, FIG. 2A is an oblique view of thepercutaneous port 200; FIG. 2B is a side cross-sectional view of thepercutaneous port shown in FIG. 2A; and FIG. 2C is a close-up of thecross-sectional view shown in FIG. 2B.

The percutaneous port 200 includes a substrate or plate 202 with coil204 joined to one surface thereof. More specifically, the plate 202defines a hole 206 therein (e.g., a first opening) and first and secondopposing and substantially planar surfaces 210 and 212 (FIG. 2B),respectively. At least a portion of an outer surface of the coils 104 isjoined to at least a portion of the first surface 210 of the plate 202through any suitable technique, such as brazing. As shown, the coil 104includes a plurality of loops 214. As described above with respect tothe percutaneous port 100 of FIGS. 1A-1C, the plurality of loops 214 ofthe coil 204 facilitate optimal tissue in-growth, enabling a strongerphysical integration of the percutaneous port 200 with the surroundingtissue, thereby mitigating issues such as inadvertent port removal andinfection.

The percutaneous port 200 provides an interface enabling internal accessto a patient in which a percutaneous port 200 is implanted. As describedabove with respect to the percutaneous port 100 of FIGS. 1A-1C, theopening 206 provides a port through which external components (e.g.,electronic devices) can access internal components (e.g., implantedsensors). The flat percutanous port reduces the vertical dimension ofthe port.

The plate 202 can have any suitable shape, such as the disc shape shownin the figures. In other embodiments, the plate 202 is square,rectangular, or polygonal. Furthermore, in some embodiments, the plate202 is made from titanium or any other suitable material. In someembodiments, the first surface 210 of the plate 202 is made from amaterial selected from nickel or any other suitable material.

The coil 204 is the same as coil 104 discussed above in relation to thepercutaneous port 100. The longitudinal axis in this embodiment isformed through the center opening of the plate 202 and is perpendicularto the first surface 210 of the plate 202.

In some embodiments, the coil 204 is arranged such that it forms aspiral around the opening 206. In some embodiments, an additional coil(not shown), as discussed above in relation to the percutaneous port100, having a distinct loop diameter from the coil 204, forms a separatespiral around the plate 202. In this embodiment, the separate spiral isinterleaved with the spiral of the coil 204. Furthermore, in someembodiments, as shown in FIG. 2C, the loops of the coil(s) at leastpartially overlap with one another. Alternatively, in some embodiments,the coil 204 is arranged as an array (e.g., a grid pattern) along thefirst surface 210 of the plate 202. In yet other embodiments, themultiple coils 214 are arranged in straight lines radiating outward fromthe opening 206.

FIGS. 3A-3D illustrate a flowchart representing a method 300 ofmanufacturing a percutaneous port, in accordance with some embodiments.The method 300 primarily discusses manufacture of the percutaneous port100 described in relation to FIGS. 1A-1C, however, a similar process canalso be used for manufacturing the percutaneous port 200 of FIGS. 2A-2C.Throughout the description of the method 300, reference will be made toFIGS. 4A-4N, which are perspective views of the percutaneous port 100being manufactured, i.e., during various stages of manufacture. Itshould be noted that while FIGS. 4A-4N show views of the percutaneousport 100 during manufacture, method 300 is not limited to such and alsoapplies to the manufacture of the percutaneous port 200.

In some embodiments, a manufacturing device (e.g., machinery including abrazing fixture 400, FIG. 4B) is coupled to a computer control system(not shown) for facilitating the manufacture of a percutaneous port. Thecomputer control system includes a processor (not shown) and memory (notshown) storing instructions for performing the method 300.

Initially, as shown in FIG. 3A, a tubular structure having an outersurface is provided (302). FIG. 4A shows a perspective view of thetubular structure 102 with the outer surface 116(b). A non-limitingexample of a tubular structure 102 is also shown in FIGS. 1A-1C. Asdescribed above, in some embodiments, the tubular structure 102 includesan outer surface 116(b) to which the coils 104 and/or 118 are joined. Insome embodiments, the tubular structure 102 is made (304) from titanium.In some embodiments, the outer surface 116 of the tubular structure 102is (306) nickel. Furthermore, although the tubular structure 102 iscylindrical in the example provided, in some embodiments, the tubularstructure 102 has (308) any suitable shape. Various other features andaspects of the tubular structure 102 and the outer surface 116 aredescribed in greater detail above with respect to FIGS. 1A-1C.

In some embodiments, the tubular structure 102 is inserted (311) onto arotatable shaft of a brazing fixture. An example of a brazing fixture400 is shown in FIG. 4B. In some embodiments, the brazing fixture 400includes one or more locking mechanisms 402-A, 402-B (e.g., for lockingthe free ends of the coil 104, FIG. 4K prior to the winding and afterthe joining steps, as discussed below), and a rotatable shaft 404. Asshown in FIGS. 4C and 4D, the rotatable shaft 404 of the brazing fixture400 is inserted into the tubular structure 102.

Next, a coil having an outer surface and comprised of a plurality ofloops is provided (312). A non-limiting example of a coil 104 is shownin FIG. 4E. In some embodiments, the coil 104 is formed (314) byproviding a center rod 504, and winding a wire (e.g., which comprisesthe coil 104) around the center rod 504. Afterwards, in someembodiments, each of the free ends of the wire is tacked (316) into thecenter rod 504. FIG. 4E illustrates the coil 104 formed by a center rod504, around which a wire (e.g., which comprises the coil 104) is woundin a spiral fashion, where the ends 506 of the wire are tacked into thecenter rod 504. In some implementations, the ends 506 of the wire arelaser tacked into the center rod 504. In some embodiments, the centerrod 504 comprises (318) a sacrificial material. Specifically, in someembodiments, the sacrificial material is selected (320) from the groupconsisting of: molybdenum and tungsten. As described in greater detailbelow, in some embodiments, the center rod 504 is later etched awayusing a chemical etchant to form the coil 104 shown in FIG. 1A. In someembodiments, the coil comprises (322) a material selected from the groupconsisting of: titanium and its alloys, nitinol, tungsten and itsalloys, molybdenum and its alloys, niobium and its alloys,cobalt-chromium based alloys, noble metals, such as platinum, iridium,palladium, silver, gold, and their alloys, and medical grade stainlesssteel.

In other embodiments, the coil 104 shown in FIG. 1A is formed by amethod not requiring the use of a chemical etchant and a center rodconsisting of a sacrificial material. For example, in some embodiments,a coil 104 is formed by twisting and/or bending a wire (e.g., a wirecomprising the coil 104). Alternatively, rather than providing a coilcomprised of a plurality of loops, some embodiments include providing aplurality of individual, unconnected rings for joining to the outersurface 116 of the tubular structure 102.

As described in greater detail above with respect to FIGS. 1A-1C, theplurality of loops of the coil has a loop diameter. In some embodiments,the loop diameter is controlled by the diameter of the center rod 504.Furthermore, in some embodiments, the center rod 504 has a non-circularshape (e.g., polygonal), which also defines the shape of the pluralityof loops. Various other features and aspects of the plurality of loopsare described in greater detail above with respect to FIGS. 1A-1C and2A-2C.

In some embodiments, an additional coil having an outer surface andcomprised of a plurality of loops (e.g., loops 121) is provided (324).Furthermore, in some embodiments, the plurality of loops of the coil hasa first loop diameter and the plurality of loops of the additional coilhas a second loop diameter, wherein the first loop diameter and thesecond loop diameter are distinct (326). An example of such anembodiment is shown in FIG. 4E, which illustrates the coil (e.g., coil104) and the additional coil (e.g., coil 118), wherein their respectiveplurality of loops have distinct loop diameters from one another. Insome embodiments, the additional coil (e.g., additional coil 118) iswound around the coil (e.g., coil 104).

Optionally, in some embodiments, prior to joining at least a portion ofthe outer surface of the coil to the outer surface of the tubularstructure 102 (as described in greater detail below), the coil is wound(328) around the tubular structure 102 in a spiral. FIGS. 4F-4Killustrate this process in greater detail. First, in some embodiments,prior to winding the coil, one of two free ends of the coil are lockedin a fixed position. For example, as shown in FIG. 4F, the coil 104 ispositioned into the locking mechanism 402-A of the brazing fixture 400,and in FIG. 4G, the coil 104 is locked (330) in a fixed position (e.g.,using a screw to tighten a clamp). Next, as shown in FIGS. 4H and 4I,the coil is wound around the tubular structure 102 in a spiral. In FIG.4H, for example, by rotating the shaft 404 of the brazing fixture 400inserted into the tubular structure 102, the shaft 404 (e.g., coupled toand powered by a motor) rotates in either a clock-wise orcounter-clock-wise direction, such that the coil 104 forms a spiralaround the tubular structure 102. In some implementations, while theshaft 404 rotates, tension is simultaneously applied to the free end ofthe coil 104. In some implementations, the coil 104 is wound around thetubular structure 102 until a predetermined unwound length of the coil104 remains. For example, as shown in FIG. 4M, after the coil 104 hasbeen wound around the tubular structure 102, an unwound excess length ofthe coil 104 remains un-joined to the tubular structure 102.

In some embodiments, the coil is arranged along the longitudinal axis ofthe tubular structure 102. In other embodiments, a plurality ofindividual, unconnected loops are arranged (e.g., in an array or otherpredefined pattern) along the outer surface of the tubular structure102.

In some implementations, after winding the coil, but before joining atleast a portion of the outer surface of the coil to the outer surface ofthe tubular structure 102, the other free end of the coil is locked(332) in a fixed position. As shown in the examples of FIGS. 4J and 4K,after winding the coil 104 around the tubular structure 102, theremaining free end of the coil 104 is locked into the locking mechanism402-B (e.g., using a screw to tighten a clamp) in preparation for ajoining process, as described in greater detail below.

In some embodiments, the additional coil is wound (334) around thetubular structure 102 in a spiral. As described in greater detail above,in some embodiments, the spiral from winding the additional coil isinterleaved (336) with the spiral from winding the coil. FIG. 1Cillustrates an example in which the distinct spirals from winding thecoil and the additional coil are interleaved. In some embodiments, boththe coil and the additional coil are simultaneously wound around thetubular structure 102.

After providing the tubular structure 102 and the coil, at least aportion of the outer surface of the coil is joined (338) to the outersurface of the tubular structure 102.

In some embodiments, the joining comprises brazing (340) at least aportion of the outer surface of the coil to the outer surface of thetubular structure 102. Brazing is a process by which two components arejoined together by heating a material (e.g., which is sometimes thematerial of the components themselves) above its melting point.Implementations sometimes use a brazing oven, which provides an inertenvironment (e.g., gas or vacuum) in which the brazing process iscarried out. The example provided in FIGS. 4-7 illustrate such a brazingprocess and the preparation involved. Specifically, after the coil 104has been wound around the tubular structure 102 and its free ends lockedinto place, the entire brazing fixture 400 containing the unfinishedpercutaneous port assembly (FIG. 4K) is placed into a brazing oven. Insome embodiments, the brazing fixture 400 is made of a high temperaturealloy (e.g., alloy 42 or 50) so that it can withstand the hightemperatures of the brazing process. In the example shown, whileapplying the high brazing temperature to the unfinished percutaneousport assembly, at least a portion of the outer surface of the coil 104and the outer surface 116 are brought to or above their melting pointand thus bonded together. In some embodiments, the outer surface of thetubular structure 102 comprises (342) a plated material, and the coilcomprises (344) a coil material, wherein the plated material and thecoil material are chemically reactive with one another. Examples of suchmaterials are described above with respect to FIGS. 1A-1C.

In some implementations, brazing is performed for a predefined period oftime that is based at least in part on a thickness of the wirecomprising the coil (e.g., coil 104), a thickness of the outer surface(e.g., outer surface 116, FIG. 1A) of the tubular structure, and thepredefined brazing temperature. For example, the predefined brazingtemperature is typically within the range of 940 degrees Celsius to 1050degrees Celsius, with a holding time between 1 to 60 minutes. As shownin FIGS. 4L and 4M, after applying the high temperature for a predefinedperiod of time, the locking mechanisms are unlocked and the brazedpercutaneous port assembly is removed from the brazing fixture. FIG. 4Nillustrates a brazed percutaneous port assembly with the center rod ofthe coil still intact. The percutaneous port 100 of FIG. 1A is anexample of a finished percutaneous port after the center rod 504 isremoved (described below).

In other embodiments, the joining comprises a welding process, such asresistance welding, laser welding and e-beam welding, whereby the coilis welded to the outer surface of the tubular structure 102.Alternatively, in some embodiments, joining comprises using a medicalgrade epoxy to bind the coil to the outer surface of the tubularstructure 102. In some embodiments, joining comprises using soldering orsolid state diffusion.

In some embodiments, at least a portion of the outer surface of theadditional coil is joined (346) to the outer surface of the tubularstructure 102, in a similar manner to that described above for joiningthe coil 104 to the tubular structure 102.

In some embodiments, after the joining, at least some of the pluralityof loops are oriented (348) at an angle to the outer surface of thetubular structure 102. Loop orientation is described in greater detailabove with respect to FIGS. 1A-1C.

In some embodiments, after the joining, any excess or remaining coil istrimmed (350). For example, as shown in FIG. 4M, the excess coil thatwas not joined to the outer surface of the tubular structure 102 istrimmed off.

In some embodiments in which a center rod is used to form the coil, thecenter rod is then removed (352). In some embodiments, removing thecenter rod (e.g., center rod 504) occurs (354) after joining at least aportion of the outer surface of the coil to the outer surface of thetubular structure 102, while in other embodiments, the center rod isremoved before the joining. In some embodiments, removing the center rodincludes (356) etching away the center rod using a chemical etchant. Forexample, the brazed percutaneous port assembly, with the center rodstill intact (FIG. 4N), is placed into a chemical etchant solution,which reacts with and dissolves only the sacrificial material of thecenter rod, leaving the tubular structure 102 and the coil 104 intact.In some embodiments, the chemical etchant is selected (358) from thegroup consisting of: sodium phosphate; aqueous ferric chloride; anaqueous ferricyanide ion solution; a soluble molybdate; and a solubletungstate.

It should be understood that the particular order in which theoperations in FIGS. 3A-3D have been described is merely exemplary and isnot intended to restrict the method 300 to the order described. One ofordinary skill in the art would recognize various ways to reorder theoperations described herein.

It will be understood that, although the terms “first,” “second,” etc.may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another. For example, a first contact could be termed asecond contact, and, similarly, a second contact could be termed a firstcontact, which changing the meaning of the description, so long as alloccurrences of the “first contact” are renamed consistently and alloccurrences of the second contact are renamed consistently. The firstcontact and the second contact are both contacts, but they are not thesame contact.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the claims. Asused in the description of the embodiments and the appended claims, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. It willalso be understood that the term “and/or” as used herein refers to andencompasses any and all possible combinations of one or more of theassociated listed items. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

As used herein, the term “if” may be construed to mean “when” or “upon”or “in response to determining” or “in accordance with a determination”or “in response to detecting,” that a stated condition precedent istrue, depending on the context. Similarly, the phrase “if it isdetermined [that a stated condition precedent is true]” or “if [a statedcondition precedent is true]” or “when [a stated condition precedent istrue]” may be construed to mean “upon determining” or “in response todetermining” or “in accordance with a determination” or “upon detecting”or “in response to detecting” that the stated condition precedent istrue, depending on the context.

The foregoing description, for purpose of explanation, has beendescribed with reference to specific implementations. However, theillustrative discussions above are not intended to be exhaustive or tolimit the claims to the precise forms disclosed. Many modifications andvariations are possible in view of the above teachings. Theimplementations were chosen and described in order to best explainprinciples of operation and practical applications, to thereby enableothers skilled in the art.

What is claimed is:
 1. An apparatus for promoting tissue in-growtharound an opening that allows continuous access through skin,comprising: a percutaneous port comprising: a tubular structure havingan outer surface that comprises a plated material; and a continuous coilcomprising: a coil material that is chemically reactive with the platedmaterial; an outer surface; and a plurality of loops, wherein the outersurface of the continuous coil that is in contact with the tubularstructure is joined to the outer surface of the tubular structure viathe plated material.
 2. The apparatus of claim 1, wherein a crosssection of the tubular structure is circular, square, rectangular, orpolygonal.
 3. The apparatus of claim 1, wherein the continuous coilforms a spiral around the tubular structure.
 4. The apparatus of claim3, further comprising an additional coil having an outer surface andcomprised of a plurality of loops, wherein the additional coil alsoforms a spiral around the tubular structure, wherein the plurality ofloops of the continuous coil have a substantially larger diameter thanthe plurality of loops of the additional coil.
 5. The apparatus of claim4, wherein the spiral formed by the additional coil is interleaved withthe spiral formed by the continuous coil.
 6. The apparatus of claim 1,wherein after joining, at least some of the plurality of loops areoriented so as to form an angle with the outer surface of the tubularstructure.
 7. The apparatus of claim 1, wherein the at least a portionof the outer surface of the continuous coil is brazed to the outersurface of the tubular structure.
 8. The apparatus of claim 1, whereinthe continuous coil comprises a material selected from the groupconsisting of titanium and its alloys, nitinol, tungsten and its alloys,molybdenum and its alloys, niobium and its alloys, cobalt-chromium basedalloys, noble metals and their alloys, and medical grade stainlesssteel.
 9. The apparatus of claim 1, wherein the tubular structure ismade from titanium.
 10. The apparatus of claim 1, wherein the outersurface of the tubular structure is made from nickel.
 11. The apparatusof claim 1, wherein successive loops of the plurality of loops arerespectively oriented to form two or more distinct angles from alongitudinal axis of the outer surface of the tubular structure.
 12. Theapparatus of claim 4, wherein the additional coil is interleaved betweenat least some of the loops of the continuous coil.